Millsaps Student Volunteers Remove Privet on Museum of Natural Science Nature Trails
Chinese privet (Ligustrum sinense) an exotic invasive plant species has become widely established through much of LeFleur's Bluff State Park. At certain ground elevations, privet plants dominate the shrub layer of the hardwood swamp forest in the park and make a nearly solid evergreen wall along portions of the Museum of Natural Science nature trails. The privet outcompetes native midstory tree species like silverbell, pawpaw, and sweetleaf. It also shades out the forest floor and prevents trilliums, maypops and herbaceous plants and wildflowers from thriving. Museum staff have been hesitant to use the broadcast application of herbicide in this area to control privet due to the effect that spray drift may have on other plants. Spray drift also poses potential hazards to aquatic animals, especially amphibians and fish inhabiting adjacent wetlands. In the spring of 2006 students from Millsaps College in Jackson undertook an environmental project in cooperation with the Museum Science to remove Chinese privet from swamp terraces along the Pearl River in the Park. Members of the Kappa Alpha fraternity and several zoology students donated 4 hours each of labor. It was an unusual type of philanthropy project for a fraternity to undertake, but the KA chapter members jumped at the idea. Dr. Liz Brandon also offered students in her Zoology class one point of extra credit for each 4 hours given to volunteer projects at the Museum.
Work began at the state champion American beech tree which is on the middle swamp terrace located between the Museum and the river. The students worked on the west side of the nature trail and removed privet on about two acres. More than 500 plants were either dug up or cut down and dragged into piles. The largest pile grew to about thirty feet long and eight feet tall. The work was done with hand tools: shovels, picks and saws. Small plants could be pulled up or dug out by the root ball, but some were mature which meant that sawing was the only practical way to remove them. Privet is an ideal invasive exotic plant, and is very tenacious of life, not unlike an unstoppable alien from a horror movie. Privet suppression will be a continuing project because plants that are dug up or sawed down often sprout from stumps and remnant roots. Birds also eat privet seeds and spread them via droppings. Brush application of concentrated glyphosate, (Roundup) on new sprouts and cut stumps is recommended as a way to kill privet or at least weaken it. Brush application poses less risk to other plants and wildlife. The result of the work is dramatic to anyone who knew the trails previous to this project.
Unobstructed lines of sight let trail users see the beautiful hardwood forest without the clutter of the privet. Two hundred foot tall sweet gum, ash and oak trees that now stand out in an open midstory populated only by the native species. The response of the native midstory and understory plant species will be monitored with interest by museum staff over the next few years. Many species that were suppressed by the privet should flourish now. We hope to continue beating back the privet and to begin removal of Chinese tallow trees, Sapium sebiferum, which are less numerous, but are equally unwelcome invasive exotic plants in this bottomland forest. Inside the Museum, visitors can see thirteen aquariums, each representative of different fish habitats, along with a large glassed-in terrarium representing the Pearl River swamp. The real swamp is just outside, down the bluff and along the trails to the Pearl. All of this lies within the city limits of Jackson. Of the 130,000 annual visitors, about half venture onto the trail system. Thanks to the work of the student volunteers on the terrace trail, more than 65,000 visitors, many of which are children, will see what a hardwood bottom forest should look like, open and not choked by invasive plant species.